Slight Networking issues....

djroketboy · 06-11-2003, 07:45 AM

Hi everyone.. i'm a

.. to both linux and this site

I just started at a small company and they had a existing network in place. I was hired to help with the in house computer/plotter/printer issues, and also service HP Plotters. So far i have done a lot of work to this place, but there are a few things that have got me completely stumped.

Here is our layout. We have about 18 computers. 2 switches, 1 linux server, and 1 file server(<--headache machine).

Our file server is a MaxAttach file storage system, which runs win2k pro w/ terminal services. I didn't set it up, but it seems to be functioning correctly for the most part (as a windows system could).

Our Linux box is a dual p3 700 w/ 512mb ram. 1 Intel dual nic (sorry, don't know alot of the model #'s off hand) and a on board Intel nic (looks to be the same model type as the dual nic).

The PC's are running a range of systems, win98, nt4, win2k, and winxp. The pc part is simple enough for me to manage.

The problem is w/ linux (IMO). I've set up samba, and have it working at a share level, i would rather have it working at a user level. but its working for now, so i really dunno if i should mess with it. But as in another post, which i tried all the recommendations. We can't ping the local LAN from the linux box using names. Ip's work, but NOT names. This is also true for WAN.

Code:

[root@linuxbox etc]# ping hotmail.com
PING hotmail.com (64.4.53.7) from 192.168.1.1 : 56(84) bytes of data.

--- hotmail.com ping statistics ---
15 packets transmitted, 0 received, 100% loss, time 13998ms

Code:

[root@linuxbox etc]# ping copy-1
ping: unknown host copy-1

Code:

[root@linuxbox etc]# ping 192.168.1.246
PING 192.168.1.246 (192.168.1.246) from 192.168.1.1 : 56(84) bytes of data.
64 bytes from 192.168.1.246: icmp_seq=1 ttl=128 time=0.228 ms
64 bytes from 192.168.1.246: icmp_seq=2 ttl=128 time=0.262 ms
64 bytes from 192.168.1.246: icmp_seq=3 ttl=128 time=0.216 ms
64 bytes from 192.168.1.246: icmp_seq=4 ttl=128 time=0.383 ms

--- 192.168.1.246 ping statistics ---
4 packets transmitted, 4 received, 0% loss, time 2999ms
rtt min/avg/max/mdev = 0.216/0.272/0.383/0.067 ms

Eventually we want to make this linux box also our web server for the store. I'll get there eventually. I would like to make sure we have everything running fine first.

1 thing i did notice when working with this lan was that the cables were NOT to T-568B standards, they were just kinda "in there" every cable was different, and i'm actually surprised they got it all too work. This has now been fixed, i put new connectors on every cable in the building.

The first thing i would like to resolve is the apparent local DNS issues we are having on the LAN.

camelrider · 06-11-2003, 08:42 AM

Have you entered the IP numbers of your DNS server(s) in /etc/resolv.conf ?

Example:
[tom@k6 tom]$ less /etc/resolv.conf
search acsalaska.net
nameserver 209.193.4.7
nameserver 209.112.160.2

The above IP's are from my provider's servers. Of course you would use your internal DNS server if appropriate.

djroketboy · 06-11-2003, 09:20 AM

yes, i have, we can brows the net just fine... it seems i'm just missing something, and really not sure what it is...

here is the resolv.conf file:

Code:

search localdomain
nameserver 192.168.1.1
nameserver 216.120.144.135
nameserver 216.120.131.34

here are some things i've tried.

1. changed all windows box's to have NetBios over TCP/IP
2. turned of the firewall
3. argh.. there were other things i tried, but can't find the post.

Looking_Lost · 06-11-2003, 09:51 AM

Another one of my funny ideas using WINS:

I've played about with the WINS server in samba. Seeing as all the windows computers can use WINS natively , set them to use samba as the sever and wrote a two line script that lets you ping by name without bothering about dns as obviously WINS is dynamic.

Only difference now on linux machine is I lping <computer name> as opposed to ping <computer name>

Don't know how wins works across different subnets but there ya go....another idea.

djroketboy · 06-11-2003, 10:14 AM

that sounds like a possibility....

are there any good books, or writeup's on setting it up?

Looking_Lost · 06-11-2003, 12:21 PM

It's really just an option in the samba config file

change and uncomment the line to
wins support=yes
and
wins proxy=yes (might not be needed)

restart samba found it better to reboot in this case as nmb can be a bit fussy sometimes when restarted. May take a few minutes for all the windows machines to register their names and IP's initially.

add the IP address of the samba server to windows machines WINS TCP/IP settings

Quote:

#!/bin/bash

hostname=`nmblookup $1 | awk '{print $1}' `
host=${hostname:9:15}

ping $host

exit

Saved that as lping and make executable and put in /usr/bin

Can now ping by hostname lping <computer_name>

You might have to change the 9 to a lesser or greater value and I'm sure their's probably a better way to script it.

Still have to use normal ping to ping by IP though unless you write a more robust script.

djroketboy · 06-11-2003, 01:45 PM

ok, i have wins up and running....

now this is even weirder, this is what i can and can't ping... BTW i'm using ping to see where my problem is overall, we are getting massive slowdowns on a random basis... so i'm just trying to cover all my bases to find out where the problem lyes....

windows can ping to each other using and linux using <computer name> & <ip>, but CANNOT ping to WAN (internet)

linux can't ping anything <computer name> NOR <ip> NOR WAN (internet)

Robert0380 · 06-11-2003, 01:59 PM

i only read the 1st thread and scanned the rest to see if what im gonna say was there...so if this has been fixed...sorry for the not-needed post:

if you want to be able to ping by host name, you could put
the hosts in your /etc/hosts file:

example hosts fle:

Code:



# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1       decatur robert.dynu.net
127.0.0.1       localhost
192.168.1.100 robert
192.168.1.103 linuxserver
192.168.1.102 fcs

well, that's my hosts file anyway, you could add the IP and
host name of each computer on your LAN, that's the hard way
but it works.

Looking_Lost · 06-11-2003, 02:02 PM

My apologies here....i looked into it a bit more and the WINS server was a bit of a red herring..a case of wrongful deduction. The command basically I'm using is nmblookup which turns out isn't dependent upon that - using WINS will generate alot of broadcast's across your network and if you were already having problems I guess it has compounded it. Turn off the WINS again and hopefully it'll go back to the way it was but the nmblookup thing should still work for internal machines

You don't have any sort of friewall running do you?

And of course you could do the host files thing above if they're all static

djroketboy · 06-11-2003, 02:25 PM

everything here used to be static, i swtiched everything to DHCP xcept for the 2 server and the printers....

ok, wins is now off...

we have a ton of "connected" equipment here, and it would be a ton of work to enter everything into a file...

excuse my ignorance, but i thought this is what NetBios/Wins was for?

I do want to say thank-you for those that have been helping, it's really really appreciated

EDIT: could it be that i don't have DNS setup correctly? or.....(running out of idea's)

As for a firewall, we are behind a Cisco router, and i have not a clue on how to operate it, i've never needed to.... Part of the contract with Trivalent is that they only open/close ports as we need.... but.. we used to be able to ping... all up until i setup the DHCP server and Samba....

Looking_Lost · 06-11-2003, 03:15 PM

Well you are resolving external hostnames by DNS you got hotmail.com to 64.4.5.37 so DNS is working

I tried pinging it do - it's down no response or else it isn't pingable

I guess you've tried www.yahoo.com and other ones?

One last go on the nmblookup is you enter nmblookup <computer_name_on_network> do you get any output? Then I'll stop harking about it

djroketboy · 06-13-2003, 12:25 PM

ok i tried the nmblookup, and it DOES work

that's one of the things i tried from a different post....

Code:

[root@taz /]# nmblookup copy-1
querying copy-1 on 192.168.1.255
192.168.1.199 copy-1<00>

i'll figure this out eventually

BTW i can replicate this on my home linux box, so it's definatly somethign i have setup wrong, if i disable DHCP and Samba, i can ping everything fine, so it's somewhere in one of those two scripts...

thanks for your help